It is advantageous in some manufacturing processes to simultaneously heat by electric induction two separate workpieces that, for example, may be different from each other and are joined together after heating.
One example of such manufacturing processes is disclosed in U.S. Pat. No. 6,825,450 B2 (Ribeiro et al.) where the two separate workpieces are an upper crown part of a piston and the second part is the lower crown part of a piston that complements the upper part and when joined together form the piston. The upper crown part may also be called the crown and the lower crown part may also be called the skirt. The complementary sides of the upper and lower crown parts are first heated, for example, by electric induction, and then joined together, for example, by simultaneously pushing and twisting the complementary sides of the upper and lower crown parts together. U.S. Pat. No. 6,637,642 B1 (Lingnau) describes one such joining process. It is advantageous to heat the upper and lower crown parts simultaneously to provide similar heating profiles in both the upper and lower crown parts for the subsequent welding process that joins the upper and lower crown parts together.
It is one object of the present invention to provide a double-sided flat inductor assembly for simultaneous induction heating of two separate workpieces in a manufacturing process.
It is another object of the present invention to provide a double-sided flat inductor assembly for simultaneous induction heating of complementary sides, or faces of two separate workpieces in a manufacturing process and rapid withdrawal of the inductor assembly away from complementary sides of the two separate workpieces to facilitate joining of the heated complementary sides.